Hydraulic-mechanical transmission



June 9, 1953 A. G.v SCHNEIDER HYDRAULIC-MECHANICAL TRANSMISSION Fild Sept. 12,- 1947 3 Sheets-Sheet 1 A. G. SCHNEIDER HYDRAULIC-MECHANICAL TRANSMISSION June 9, 1953 3 Sheets-Sheet 2 Filed Sept. 12, 1947 June 9, 1953 A. G. SCHNEIDER HYDRAULIC-MECHANICAL TRANSMISSION v 3 Sheets-Sheet Filed Sept. 12, 1947 My 40 a M 15 Patented June 9, 1953 HYDRAULIC-MECHANICAL TRANSMISSION Adolf G. Schneider, Muncie, Ind., assignor to Schneider Brothers Company, Muncie, Ind., a

copartnership Application September 12, 1947, Serial No. 773,595

12 Claims. 1

This invention relates to variable speed transmissions and has particular reference to the combination of a hydraulic torque converter with mechanical power transmitting means, in order to obtain better operating characteristics than would be obtainable from either the hydraulic or mechanical means alone, the present transmission being an improvement on that disclosed in my Patent 2,308,547, issued January 19, 1943.

The principal object of my invention is to provide a hydraulic transmission in combination with an auxiliary gear drive which will permit the torque obtained from the torque converter to be transmitted to the driven shaft either with direct driv or at a certain gear ratio, and more particularly to provide for smooth and easy shifting to and from forward, neutral and reverse, using only a counter-shaft reverse gear box, and

applying a brake on the turbine shaft while shifting.

A further object is to provide such a combined transmission of a simple design, with well known tried and proven parts, to reduce cost and to obtain a trouble-free unit.

Other objects of the invention will appear from the following description in which reference is made to the accompanying drawings, wherein- 1 is a more or less diagrammatic longitudinal section through a transmission made in accordance with my invention, this figure including, for convenience of illustration, an operating diagram of the transmission in which appear sections of the two brakes, and both a plan view and vertical section of the shift lever on the steering column and a section of the two control valves of which one is shown as operated by said shift lever;

Fig. 2 is a section on line 22 of Fig. 1;

Fig. 3 is a section of the control valves shown in high speed position;

Fig. 4 is a more or less diagrammatic view similar to Fig; 1 showing a variation of the trans-- mission made in accordance with my invention;

Figs. 5 and 6 are sections of the two brakes on the correspondingly numbered lines of Fig. 4, these sections being like" those appearing in the lower portion of Fi l, and

Fig. 7 is another diagrammatic view of a planetary gear set and two-speed countershaft gear box with reverse gearing, which is combinable with a hydraulic turbo drive like that of Fig. 1.

Similar reference numerals are applied to corresponding parts in these views.

Referring first to Figs. 1 to 3, 9 is the driving shaft, which may be the crankshaft of an internal combustion engine orany other prime mover, and i0 is the driven shaft. Ii and i2 are coaxially aligned shafts between shafts 9 and iii. The flywheel i3 turning with the crankshaft c carries a ring gear [4 meshing with one of each pair of dual planetary gears I? provided on a cage 56 mounted on the cover or housing plate i'l integral with the pump impeller it of the torque converter; Theother of each pair of the dual planetary gears i5 meshes with the sun gear is mounted on shaft II to which turbine wheel 2!) of the torque converter is connected. The

reaction member 2| of said converter is mounted on a sleeve 22 which is rigidly attached to the stationary housing 23 that encloses the torque converter and flywheel and maybe formed integral with a housing enclosing the rest of the transmission. Ring gear 24 of a second planetary gear set is mounted on the rear end of turbine shaft H. Intermediate shaft 12 carries a planetary cage 25 and provided thereon are planetary gears 26 meshing with ring gear 24 and also with a sun gear 2?. Integral with the sun gear 2? is a sleeve 28- and mounted thereon is a brake drum 29. Brake band 30 cooperates with brake drum 29. Ring gear 24 also serves as a brake drum and has a cooperating brake band 3!. Planetary cage 25 carries an extension 32 on which is carried one set of discs of a disc clutch 31- the other set of intermediate discs being carried on the inside of drum 29. Clutch serves to connect or disconnect the planetary cage 25 and the sun gear 21. Drive gear 3% is mounted onintermediate shaft [2 and meshes with gear 35 on countersh'aft 36; Gear 37 turning with gear 35 meshes with a reverse idler gear indicated in dotted lines at 38, which in turn meshes with gear39 free to turn on the driven shaft it. Hub 40 is mounted on driven shaft iii and shift ing collar M is free to slide on splines on hub it. Moving shifting collar 4-! to the left will engage clutching teeth 42 of gear 34' for forward drive, and moving collar M to the right will engage clutching teeth 43 of gear 39 for reverse drive. The collar 4| is shown in Fig. 1 in the middle or neutral position.

The operation of brake bands 3i and 3i is clearly shown in the lower portion of Fig. 1. Gear shift lever 44 is arranged under and adjacent the steering wheel of the car on the steering column in the usual way and, while in actual practice it serves as a remote control for the shifting collar 4|, in this diagrammatic illustration it is shown as arranged to have a substantially direct operating connection with the shifting collar 4|. Thus, when lever 44 is raised to the dotted line position shown in the lower portion of Fig. 1, to disengage it from one of the notches in the keeper plate 45, toward which it is urged by spring 46, lateral movement of shift lever 44 from the neutral (N) position to forward (F) or reverse (R) drive position, causes end- Wise movement of rod 48 and corresponding movement of shifting collar 4 because the latter is connected to rod 48 by means of a fork 49 and the rod 46 is operatively connected to shift lever 44 through a bell-crank lever 50 and connecting rod 5|. Now, lever 44 is connected through a link 52 with one of two control valves 53 and 54. Lever 44 operates valve 53, and an electric solenoid 55 operates valve 54. An oil pump 56 suitably driven by th engine of the car delivers oil under pressure from a reservoir through line 5'! to the body of valve 54 and thence to the body of valve 53. Therefore, when shift lever 44 is raised, as above stated, valve 53 is also raised and oil is delivered under pressure from the body of valve 53 through line 58 to apply brake band 3| so as to hold turbine shaft stationary. The band 3| has one outwardly bent end of its metal backing abutting an adjustable set screw 59, and has the other end movable with a bell-crank lever 60 which is operable by means of a piston 6| working in a cylinder 62 to which one branch of line 58 is connected. A coiled compression spring 63 normally urges piston 6| to a retracted position releasing the brake, and it is only when control valve 53 is shifted upwardly with lever 44, as stated, that the oil under pressure is delivered to cylinder 62. Hence, it is clear that the brake is applied to turbine shaft only while shifting to and from forward, neutral and reverse. While the brake is applied to turbine shaft H by band 3|, band 36 is also released because oil under pressure is simultaneously delivered through the other branch of line 58 and body of valve 54 and line 64 to cylinder 65 to force piston 66 back against resistance of brake applying spring 61. The band 30, in other words, is like band 3| but the oil pressure operation thereof is reversed. The band 30, when exerting a braking action, serves to hold the sun gear 21 stationary. When the turbine shaft I is held by band 3|, and band 36 is released and clutch 33 is also released, the intermediate shaft I2 is free floating and shift collar 4| can be moved easily to forward or reverse position and back to neutral in the gear box. After the shift is made, lever 44 is returned by spring 46 to its former retracted position so that control valve 53 is also returned to its lower position releasing brake band 3| and allowing band 36 to be applied under spring pressure. The clutch 33 is also operable by oil pressure as clearly shown in Fig. 1. Direct drive valve 54 is moved to the position shown in Fig. 3 by energization of solenoid 55 when high range is desired. Solenoid 55 can be energized in any suitable manner, that is, automatically in response to a predetermined speed of the vehicle or by manual control. High range is obtained by delivering oil under pressure to cylinder 68 through line 68' from the body of valve'54, and simultaneously delivering oil under pressure to cylinder 65, clutch 33 being thereby engaged by piston 69 moving forward against resistance of its return spring 10, and brake band 30 being released by the backing up of its spring actuated piston 66.

In operation, therefore, with the shifting collar 4 4| and shift lever 44 in neutral position there is no drive transmitted to driven shaft I0, although driving shaft 9 and flywheel l3 and ring gear l4 may, for example, be running at idling speed. The lever 44 is held in the middle notch of the keeper plate 45 by the spring 46. There is oil pressure at that time in the line 51, and the pressure is communicated through line 1| to the body of valve 53, but with the valve 53 in the lower position, there can be no flow of oil from the valve. Hence, the shifting brake band 3| is free, high range clutch 33 is free, and the low speed brake band 30 holds the drum 29, because th band 30 is applied by pressure of the spring 61, and is arranged to be released by oil pressure. To shift into gear, lever 44 must be raised out of its notch in the keeper plate. 45 and in so doing, valve 53 is also raised and allows oil to flow from the pump 56 through line 51 to valve 52 and thence through line 7| to valve 53, which, being raised, allows the oil to pass through line 58 back to valve 54, and thence through line 64 to the cylinder so as to move the piston 66 against the resistance of spring 61 to release the band 30. It will also be noticed that the line 58 has another branch through which oil under pressure is delivered to the cylinder 62 to move the piston 6| against the resistance of its spring 63 to apply the band 3| so as to hold the drum 24, and thereby hold the turbine shaft stationary. The gear shift can now be completed by moving lever 44 into the forward or reverse position marked F and R. in the upper portion of Fig. 1, because band 3| is holding the drum 24. band 36 is released, and clutch 33 is released, allowing shaft |2 to be free so that the shifting collar 4| can engage teeth 42 or 43, as desired. Assuming lever 44 has been moved to the forward position and released, the spring 46 returns it to its lowered position and it engages in a registering notch in the keeper plate 45. Valve 53 is accordingly moved downwardly shutting off the oil now in line 58 and bleeding oil pressure from cylinders 62 and 65 so that band 3| is released and band 30 is engaged under the pressure of spring 61. The vehicle now moves forward at low speed. To shift into high speed or direct drive, valve 54 is moved upwardly by energization of the electrical solenoid 55, allowing oil under pressure from line 51 to pass through the valve 54 to lines 64 and 69 that extend to cylinders 65 and 68, respectively. Oil delivered to cylinder 65 under pressure releases the band 30 and oil delivered under pressure to cylinder 68 engages the clutch 33. The vehicle now runs at high speed because the sun gear 21 and carrier 25 are turning at the same speed due to the engagement of clutch 33, and because the bands 30 and 3| are both released. In other words, the entire planetary gear set turns as a unit, and shafts IO, U and I2 turn at the same speed. Obviously, low and high gear ranges in reverse are also obtained in a similar way when the shift lever 44 is moved to the other extreme position marked R in Fig. 1. The shifting brake 3| is always applied automatically whenever the lever 44 is raised to the shifting position. The same is true regarding the automatic disengagement of brake 30, so that the sun gear 21 and planetary carrier 25 are free floating. Shifting collar 4| is therefore movable freely in either direction to engage or disengage clutch teeth 42 or 43 without effort, there being no torque or drag present in the free floating shaft I2.

The modified or alternative construction disegeamaa closed: Eigsia :to: 6: incorporates-the ssametbasi'c reaturesaas .the 'transmission'tof l'rli igs. E1=to ?-3,f-:but omits the rplanetary gear set :in :front .of the torque '3 converter and includes a dual planetary gear fset behindit. .Pa1tsin:'FigS. i4"toz-'6.correspending touparts in Figs. .lto.3=fhave :beerrscorresponclingly numbered. Thus, the :itlriving :and driven shafts are sfla and l flmirespectively, and the turbine shaft f-lS 1 51a and the rintermediate shaft we. .The ifiy-Whecl 13a :inthis "form has thezpum'p impeller 2 l fla itirectly :conneotedtherewith and cooperating with. the turbine wheel-26a and; reactiommember 12'! a. AThe latter 'is married on-ra sleeve $2241 rigidly. attached to the stationary housing 23a. The jplanetary cca'rrier 1 89 is mountednon the turbine shaft its and carries pairs of intermeshed planetary ipinionigears 8 l, (meet each meshing withering.igeari thoand the other with sun gear 33. Ring gear 32::ismounted on intermediate shaft tilewhich in turn drives the'rdrivenzshaft l 8a in forward or. reverse direction through the gearing inithesgeartboxnmmbored 3 m tom-3a to correspond with: the numbering of the parts 3 1 .t'43 inFig. l. Abrakedrum 84- :is provided on the planetary cage =89, and another brake drum-'85 iszproviued ion a 'tubular extensiona tt of the sun gear 83. A 'discsclutchrfil isprovided between the brake drumifihtandthe hub extension $33 of the brake drum. and planetarycarrier 8 toconnect or'clisconnect the planetaryxcarriertth and sun gear t3. 1A brake band 89 cooperates with "brake drum 85 and corresponds in its construction :and :mode of operation tothe'brake "band 39 :of :Fig. 1, and therefore the means .forsonerating' this bancl'has been correspondinglynumberedfStwto 63a. The brake bancltt cooperating with brake drum 35 corresponds in construction and mode of: operation to the brake band 30 of Fig. land the means for operating the :same has been numbered correspondingly Sta tot'i'a. The oil lines 53a and Ma illustratedin Figs. 7 "and 8 correspond to the lines 58 and fi l of Figs. 1 and 3, andit should, of course, be understood that thesamernanually operable shift lever-"4t and solenoid andcontrol valv-esvts :and 5tdisclosediin-Figs..:1 and. 3, are employed in connection with the -?transmission of Figs. 4- to v6.

The operation-of the transnrissionsotFigs-43m 6 is quiteasirnilar to thatJpreviouslysclescribed; the planetary converter clrive being merely a replaced by. a plainconverter and. thevrear, planetary. gear set being merely replaced by a dualplanetarygear set. iTheconntershatt reversegearsct is the-same inboth transmissions. Thus-When thegear shift leVerWt is raisecl toithe dottedlineipcsitionshown inithelower portion of the brakeband fiais applied holdingthe planetary cage thansjpturbine shaft i la 1 stationary, the intermediate: shaft 1 2a under these circumstances bein iree floating-es in 'thercase of the other transmission sothat'the shift collar ilazcan be moved inieitherzdirection freely to and from for-ward, neutral,correverse position. When brakebandat is applied byspring pressurerholdingthe sun gear 83 stationarygthe turbineshaft: i la drives theplanetary:carrie zafi and drive is transmitted from it through the nlual planetary-gears-m .to-the ring gear 82 sothat the intermediate shaft t driven ata speed lower than the turbine shaft 5 ta, -io1- ioxv speed driving of driven shaft vlila, similarly-as-in the operation of the other transmission. In-this low speed drive, clutch ti it= will behunderstood' is disengaged similarly-as intheoperation-ofclutch 33 in- -F ig. 1 in t'he other i-transm-is'sion. Hence,

whentbrake band'zwzis disengaged .by the admission iOf'OiI-JIIIdBI' pressure .to cylinder a (Fig.6) and clutch 81. is :at thei'sam'e time engaged. like clutch 33 of Fig. the' snn :gear 831 connected with the planetary carrier 83 so that the-intermediate isha'ft I'Zaandthe' turbine shaft 1 I! were caused to .run together "at the ':same "speed, the dual planetary gear setlBI being locked. In'the operation of 5 this transmission rass in' the opera tion of the other, the fact that the shitt lever 46 must be raised to the dotted line position shown irrh lglliiinsures theapplication:oflthebrakeband 8'9 "tot-hold theturbinesshai-t H aa'stationaryfduring the .shifting'operation: sozassto .providefor smooth and :easy shifting to land r-from f forward, neutral reverse.

Referring r neirtl-tolFig; 7, it'will :be understood that thetplaneta'ry gear set' an'dttwo speed countershattrgear ibox with reverse gearingshown here is "combinable with zzafhydraulic turbo drive like that-ofS-Fig. L1. lHence, sl'-xaft.al i-bsof Fig. 'l corresponds to ishaft t :ofiFig. 1, aintermediatesshaft ltbitoi i2,ianxi drivensshaft to M. .Theparts numbered 224'b-:33bcorrespond to parts"2 l-33 in :Fig. l sand .zparts nth-tel) correspond to parts 168- 718. However, .the gear box shown herezris different from that of 1 and ;-re quires f-tWo shifting rcollars :MI and 241, col lar 7.1M :corres ondingcto cotlar #5 :of Fig-land being :operable :with thezrgea'r shi'ftz'lever M in: a similar wayzso asz'to release Lband rfifi'brand apply band :3'i'b When-theficollar i 'll :is shifted to or from forward, neutral, rand reverse, whereby to hold the turbine :shafti I l'bwhilethe shiftoccurs. The two collars M1 and M! are both-'showntin neutral =nosition. Collar :14 I, .li'ke rscollar F5 is arranged to .shifttfrom neutral to terward tor reverse by :moving .to the. right 501' ulett, rcepectively, from'itheipositionvshovvn. flcliar 2 H vie moved Ieither toiithe left shandtposition. for high gear, or t'o the:rlghtizhan'd" positions'forLlow. gear, as :desired. The-markings f-F .a11d fR for collar Mi indicatei foiwarhzarrcl :re'v-erse driveitpositions, respective Elie markings high and .filew indicate, snectiveiyfihighcand:low gea nositions tor GOHaT'iQQ! I Inasmuch as :the gearzng usher-v11 in the Lg-ear Ibex :iotherwise conventional it ::is belleved thatia:mcretietailed'nescription.is'uhnecessary. LThematentable' noveltyrlies in' its use in the eeneralscom-bination.

In operation, v iortv :speed Jtlrive ilis obtained by shittingicollar tel toitlme;lett to 'clutc'h teeth 13% ofibushin .186'fixvithhits-splines Hi1, and-collar til ls moved tOi he l 'htengaging. teeth t6 1ntegraliwith gearitet. i Shaft rtwthen drives through gears l- B5, its 'a n'zl I 93. :Theilatter,..being connected tocotlar t ti transmitsaarive to driven shaft ttth, we oh I then runs -a't a reduced- -speed relative t'o shaft l Z-b. Kn h-igh speed, collar M i remains th leftfhan'dpositicn but collar 24! is moved tothe leftg'engagingfteeth it? of gear Hi4. lhen-shattfib and gear t l ltransm it drive throu'gh teeth: lfl'laa'nd coliariifil ztos bu'shing we, and "thence through teeth Etilhaand :collar Mi to driven shaft Nib, which accordinglyiturnsat the samecspcedas shaft r5212. When-collar B ll is moved in hlah-or iow speed position the: clutch 33b and band 30b are released momentarily as describediabo'v-eihifr ldltOiF g...1ifor. vlntchiet and band 5w, zibut 'aviti out .abrak ng and i'holdmg the turbine sshaft H b, zthe .synthronizer 11:68 in coilaii 24 ltiservin'grto imalee fon easyrshiftingiw-ithoutlclashing iof (g ars. [It willazbe'zclear that-when elthertgear ratio 'sel'e'cte'a'in the rearaboxsthe drivensshaft stZb xof the xplanctary tggear wet scan be made to run either at the same speed as the turbine shaft H b or at a reduced speed, thereby giving a four speed transmission with a two speed box and obtaining moreover easy shifting for all speeds.

It is believed the foregoing description conveys a good understanding of the objects and advantages of my invention. The appended claims have been drawn to cover all legitimate modifications and adaptations.

I claim:

1. A transmission comprising in combination with driving and driven elements, a hydraulic turbo drive comprising at least a pump impeller and a turbine wheel, means providing a driving connection between said pump impeller and said driving element, a planetary gearing and a reverse gearing interconnected for transmitting drive from the turbine wheel to the driven element as a direct drive or as a gear ratio drive, said reverse gearing including a manually shiftable element shiftable to different positions for forward, neutral, and reverse, said planetary gearing including a ring gear with a brake drum thereon driven by said turbine wheel, planetary gears meshing with the ring gear and mounted on a carrier transmitting drive to the driven element, and a sun gear meshing with the planetary gears and carrying a brake drum and a clutch means, said carrier carrying a second clutch means operatively associated with said first clutch means, brake bands operatively associated with said brake drums, means to engage and disengage said clutch means, and means to engage and disengage said brake bands.

2. A transmission comprising in combination with driving and driven elements, a hydraulic turbo drive comprising at least a pump impeller and a turbine wheel, means providing a driving connection between said pump impeller and said driving element, a planetary gearing and a reverse gearing interconnected for transmitting drive from the turbine wheel to the driven element as a direct drive or as a gear ratio drive, said reverse gearing including a manually shiftable element shiftable to different positions for forward, neutral, and reverse, said planetary gearing including a ring gear with a brake drum thereon driven by said turbine wheel, planetary gears meshing with the ring gear and mounted on a carrier transmitting drive to the driven element, and a sun gear meshing with the planetary gears and carrying a brake drum, brake bands operatively associated with said brake drums, means to engage and disengage said brake bands, and means for releasably locking said planetary gearing to turn as a unit.

3. A transmission as set forth in claim 2, wherein the means for transmitting drive from the drive element to the pump impeller comprises a planetary gear unit, of which one element is connected with the driving element, another element is connected with the pump impeller, and another element is connected with the turbine wheel.

4. A transmission comprising in combination with driving and driven elements, a turbine ring type torque converter comprising a pump impeller, a turbine wheel, and a reaction element, means providing a driving connection between said pump impeller and said driving element, a planetary gearing and a reverse gearing interconnected for transmitting drive from the turbine wheel to the driven element as a direct drive or as a gear ratio drive, said reverse gearing including a manually shiftable element shiftable to different positions for forward, neutral, and reverse, said planetary gearing including a ring gear with a brake drum thereon driven by said turbine wheel, planetary gears meshing with the ring gear and mounted on a carrier transmitting drive to the driven element, and a sun gear meshing with the planetary gears and carrying a brake drum and a clutch means, said carrier carrying a second clutch means operatively associated with said first clutch means, brake bands operatively associated with said brake drums, means for applying the brake band to the firstmentioned brake drum in the shifting of the manually shiftable element to and from forward, neutral and reverse, means to engage and disengage said clutch means, and means to engage and disengage the brake band on the second brake drum.

5. A transmission comprising in combination with driving and driven elements, a turbine ring type torque converter comprising a pump impeller, a turbine wheel, and a reaction element, means providing a driving connection between said pump impeller and said driving element, a planetary gearing and a reverse gearing interconnected for transmitting drive from the turbine wheel to the driven element as a direct drive or as a gear ratio drive, said reverse gearing including a manually shiftable element shiftable to different positions for forward, neutral, and reverse, said planetary gearing including a ring gear with a brake drum thereon driven by said turbine wheel, planetary gears meshing with the ring gear and mounted on a carrier transmitting drive to the driven element, and a sun gear meshing with the planetary gears and carrying a brake drum, brake bands operatively associated with said brake drums, means for applying the brake band to the first-mentioned brake drum in the shifting of the manually shiftable element to and from forward, neutral, and reverse, means for releasably locking said planetary gearing to turn as a unit, and means to engage and disengage the other brake band.

6. A transmission as set forth in claim 5, wherein the means for transmitting drive from the drive element to the pump impeller comprises a planetary gear unit, of which one element is connected with the driving element, another element is connected with the pump impeller, and another element is connected with the turbine wheel.

7. A transmission comprising in combination with driving and driven elements, a hydraulic turbo drive comprising at least a pump impeller and a turbine wheel, means providing a driving connection between said pump impeller and said driving element, a planetary gearing and a reverse gearing interconnected for transmitting drive from the turbine wheel to the driven element as a direct drive or as a gear ratio drive, said reverse gearing including a manually shiftable element shiftable to different positions for forward, neutral, and reverse, said planetary gearing including a ring gear with a brake drum thereon driven by said turbine wheel, planetary gears meshing with the ring gear and mounted on a carrier transmitting drive to the driven element, and a sun gear meshing with the planetary gears and carrying a brake drum, brake bands operatively associated with said brake drums, spring means normally holding one of said brake bands engaged, fluid pressure operated means for disengaging said band, spring means normally holding the other brake band disengaged, fluid pressure operated means for engaging said band, fluid pressure operated means for releasably locking said planetary gearing to turn as a unit, a source of pressure fluid supply, and valve means for controlling the delivery of fluid from said source to said fluid pressure operated means and drainage of fluid therefrom.

8. A transmission comprising in combination with driving and driven shafts in coaxially spaced relation, a turbine shaft and an intermediate shaft coaxially arranged therebetween, a hydraulic turbo drive comprising at least a pump impeller driven by the driving shaft and a turbine wheel mounted on the turbine shaft, a planetary gear set comprising a ring gear connected to and turning with the turbine shaft, a sun gear, and planetary gears meshing with the ring gear and sun gear and carried on a carrier connected to and turning with the intermediate shaft, a brake drum turning with the ring gear and having a brake band surrounding the same to hold or release the turbine shaft, the planetary carrier carrying a clutch means, said sun gear carrying a brake drum and a second clutch means in cooperating relation with the first clutch means, a brake band surrounding the second drum to hold the sun gear stationary when not clutched to the intermediate shaft, means to engage and disengage the second brake band, means to engage and disengage said clutch means, reverse gearing interposed between the intermediate shaft and driven shaft, including shifting mechanism to select forward, reverse, or neutral, a shift lever connected to operate said shifting mechanism, and means connected to operate with the shift lever the first-mentioned brake band.

9. A transmission comprising in combination with driving and driven shafts in coaxially spaced relation, a turbine shaft and an intermediate shaft coaxially arranged therebetween, a hydraulic turbo drive comprising at least a pump impeller driven by the driving shaft and a turbine wheel mounted on the turbine shaft, a planetary gear set comprising a ring gear connected to and turning with the turbine shaft, a sun gear, and planetary gears meshing with the ring gear and sun gear and carried on a carrier connected to and turning with the intermediate shaft, a brake drum turning with the ring gear and having a brake band surrounding the same to hold or release the turbine shaft, said sun gear carrying a brake drum, a brake band surrounding the latter drum to hold the sun gear, means to engage and disengage the second brake band, means for releasably locking the planetary gearing to turn as a unit, reverse gearing interposed between the intermediate shaft and driven shaft, including shifting mechanism to select forward, reverse, or neutral, a shift lever connected to operate said shifting mechanism, and means connected to operate with the shift lever the first-mentioned brake band.

10. A transmission comprising in combination with driving and driven elements, a hydraulic turbo-drive comprising at least a pump impeller and a turbine wheel, an intermediate shaft arranged between the driving and driven elements driven by the turbine wheel, a gearbox comprising gears for forward and reverse drives adapted to be interconnected by positive engaging means for transmitting forward or reverse drive selectively from the intermediate shaft to the driven element, said gearbox including a shiftable element shiftable to difierent positions for selection of forward, neutral and reverse, friction clutch means behind the turbo-drive, brake means connectedso as to be operable in the shifting of said shiftable element to brake the turbine wheel during shifting, and means connected so as to be operable in shifting of said shiftable element to disengage said clutch means, whereby to provide in the intermediate shaft a floating member in the transmission train between the turbine wheel and the final driven element.

11. A transmission as set forth in claim 10, including a planetary gearing, comprising at least three elements, wherein said friction clutch means is arranged on and between the elements of said planetary gearing.

12. A transmission comprising in combination with driving and driven elements, a hydraulic drive comprising at least a pump impeller and a turbine wheel, an intermediate shaft arranged between the driving and driven elements driven by the turbine Wheel, a planetary gearing comprising at least three elements, one gear element of which turns with said intermediate shaft, and friction clutch means on and between said elements adapted to lock the planetary gearing so as to turn as a unit, and a gearbox comprising forward and reverse gears adapted to be interconnected for transmitting drive selectively from the intermediate shaft to the driven element, said gearbox including a manually shiftable element shiftable to different positions for selection of forward, neutral and reverse, brake means connected so as to be operable in shifting of said shiftable element to brake the turbine wheel during shifting, and means connected so as to be operable in shifting of said shiftable element to disengage said friction clutch means of the planetary gearing during shifting, whereby to provide in the intermediate shaft a floating member in the transmission train between the turbine wheel and the final driven element.

ADOLF G. SCHNEIDER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,224,884 Schneider et a1. Dec. 17, 1940 2,281,118 Smirl Apr. 28, 1942 2,298,648 Russell Oct. 13, 1942 2,308,547 Schneider Jan. 19, 1943 2,316,390 Biermann Apr. 13, 1943 2,324,733 Smirl July 20, 1943 2,328,392 Neracher Aug. 31, 1943 2,332,593 Nutt et a1. Oct. 26, 1943 2,333,681 Schneider Nov. 9, 1943 2,343,955 Cotterman Mar. 14, 1944 2,408,008 Tipton Sept. 24, 1946 2,414,359 Carnagua Jan. 14, 1947 2,541,391 Weiss et a1. Feb. 15, 1951 

